The present invention relates to a control unit for a vehicle and a total control system therefor, and more particularly to a control unit for a vehicle and a total control system therefore so as to control the engine, transmission, brake, electronic throttle, suspension and the like.
In recent years, a control unit having a single-chip micro-computer is used in vehicle control. The single-chip micro-computer incorporates memories (ROM, RAM and so on) required by calculation of the central processing unit (CPU). Therefore, there is an advantage in that the control unit can be miniaturized as a whole, being easy in use and high in processing speed.
However, the conventional technology has a disadvantage in that expanding the control unit is considerably limited when the software and/or hardware happen to be changed due to changes in the control specification. Further, there is a disadvantage in that the software program must be made under hardware limitations when a single-chip micro-computer is used in the vehicle control, and especially whenever fuel cost or cleaning of engine emissions is to be improved, increases in the number of input/outputs and upgrading of functions are indispensable and all the hardware and software needs to be renewed.
Furthermore, since the control software program written in the ROM for performing various controls is represented in an assembler language, the contents and the production technique of the program cannot be understood except by an expert in the field; in other words, such a program is useful only to an individual. Therefore, no one except an initial programmer actually participating in the production stage of the application software program can understand the detailed contents of the software program. When there is a need to add other functions to the application software program, a new program must be written from the beginning.